Some MOSFETs are designed to sustain a high operating voltage. The gate dielectric breakdown voltage (Vbd) of some MOSFETs with a broader range of Vbd (referred to as “tailing”) suffers a reliability issue. For example, a high voltage (HV) MOSFET device with a poly finger structure often suffers such a Vbd tailing. Some devices previously designed to increase the Vbd resulted in a larger device pitch, an increased threshold voltage Vt, or gate oxide thinning at the corners, which induces unstable or unwanted device performance.